This video from the USA says about itself:
In December of 2006, the Central Park Zoo reared and released 450 Puerto Rican Crested Toad tadpoles in a man made pond in Puerto Rico’s Guanica State Forest.
From the Miami Herald in the USA:
Metrozoo tadpoles sent to breed in Puerto Rico
HUNDREDS OF PUERTO RICAN CRESTED TOAD TADPOLES WILL BE FLOWN FROM MIAMI TO THEIR NATIVE LAND, WHERE BIOLOGISTS HOPE TO BREED THE RARE SPECIES
Posted on Tue, Dec. 04, 2007
BY JENNIFER LEBOVICH
Several hundred Puerto Rican crested toad tadpoles hatched at Miami Metrozoo last week are making a big leap in survival of the amphibian.
The tadpoles will be boarding a plane Tuesday, en route for Puerto Rico, where biologists hope they will repopulate the dying species.
In 2004, the Miami-Dade zoo got six toads as part of a captive breeding program. At the time, there were fewer than 250 of the Puerto Rican crested toads in the wild. It’s the only toad native to Puerto Rico.
Puerto Rico: Tropical frog battles to survive as climate change takes its toll: here.
Kihansi Spray Toad in Tanzania: here.
The Bronx Zoo has a put a most unusual frog on display: the Kihansi spray toad. For one thing, the Kihansi spray toad survived on only 5 acres in the Kihansi gorge in Tanzania, adapted to the areas’ unique and constant mist from the gorge and a waterfall. For another, female Kihansi spray toads give birth to live young, instead of laying eggs. Finally, the Kihansi spray toad is extinct—at least in the wild: here.
One hundred Kihansi Spray Toads have been flown to their native Tanzania after a close brush with extinction, reports the Wildlife Conservation Society (WCS): here.